5T/H Stainless Steel MVR Evaporator Oslo Crystallizer Used In NaCl Indutries
A stainless-steel MVR (Mechanical Vapor Recompression) evaporator integrated with an OSLO (draft-tube baffle) crystallizer, engineered for NaCl brine concentration and crystal growth at a nominal 5 t/h water removal. Recompressing secondary vapor as the heating medium delivers low OPEX, stable supersaturation, and consistent salt quality for edible and industrial grades.
Key Benefits
- Energy saving: Electric-driven MVR minimizes fresh steam after start-up.
- Crystal quality: OSLO circulation promotes larger, well-formed NaCl crystals with narrow PSD.
- Scaling control: Optimized ΔT/LMTD, high-velocity loops, antiscalant dosing, and CIP-ready design.
- Food/industrial compliance: SS316L wetted parts with hygienic finishes; duplex/Ti optional for chlorides.
- Continuous uptime: PLC/HMI recipes, alarms, historian, and remote diagnostics for 24/7 operation.
Process & Thermal Economy
Purified brine is evaporated under vacuum; the MVR compressor raises vapor temperature and recycles latent heat. The OSLO crystallizer operates at controlled slurry density and residence time to stabilize supersaturation and crystal growth while keeping specific energy consumption low.
Materials & Sanitary Design
Wetted parts in SS316L (duplex/SS2205 or titanium available). Drainable layouts, smooth finishes, and validated CIP support edible salt production and robust industrial service.
Process Overview — NaCl Brine to Product
-
Brine polishing: dissolver → softening (Ca/Mg removal) → clarification/filtration → polishing filter. - MVR evaporation (vacuum): compressor discharge sets ΔT; shell pressure defines boiling point.
- OSLO crystallization: draft-tube circulation; seed management for target crystal size and clarity.
- Solid–liquid separation: pusher/peeler centrifuge; mother-liquor recycle.
- Drying & sizing: fluid-bed/vibratory drying; screens/polishers; optional iodization/anti-caking.
Key Components
- MVR evaporator (falling film / forced circulation) with vapor–liquid separator
- Mechanical vapor compressor (turbo/Roots) with VFD for ΔT/capacity control
- OSLO crystallizer with draft tube, circulation pump, and slurry density control
- Preheaters, surface condenser, vacuum/NCG handling skid
- PLC/HMI/SCADA; instruments (T/P/flow/conductivity/level/solids); CIP skid & antiscalant dosing
Performance & Sizing
| Parameter | Typical Target / Range* |
| Evaporation rate | 5 t/h (water removal), adjustable via compressor VFD |
| Operating mode | Vacuum, continuous |
| NaCl purity (dry) | ≥ 99.2% (up to 99.7% with enhanced purification) |
| Crystal size bands | Fine 0.2–0.5 mm; Table 0.5–1.2 mm; Coarse 1.2–2.5 mm |
| Electric use (MVR) | ~15–40 kWh per ton H₂O evaporated (duty/CR dependent) |
| Fresh steam demand | Very low after start-up (backup/ancillary only) |
| Materials | SS316L wetted; duplex/SS2205 or Ti optional |
*Performance depends on brine composition, scaling tendency, compression ratio, and crystallizer design.
FAQ
Why choose an OSLO crystallizer for NaCl?
OSLO’s draft-tube circulation supports growth of larger, uniform crystals with low fines, improving centrifuging and drying.
Can this line produce edible-grade salt?
Yes—with proper brine purification, hygienic finishes, and iodization/anti-caking dosing, edible-grade specs are achievable.
How is scaling controlled?
Softening and filtration upstream, optimized ΔT/velocity, antiscalant dosing, and scheduled CIP maintain heat-transfer rates.
Application
